1. Field of the Invention
This invention relates to the feeding, in proper position and orientation, of parts essentially flat in their general shape, particularly transmission shaft dogs, to an automatic machine for welding the dogs onto the shafts.
2. Description of the Prior Art
Dogs are usually conveyed on edge along a vibrating rail to a nonvibrating grip, situated at the end of the rail, which holds a reserve supply of several dogs. The dog lying at the end of the reserve periodically drops down several millimeters to offer resistance to the part-holder of the automatic machine that moves up to grasp it. The grip comprises two retractable retainers which hold the first dog and are pushed away by two fingers on the part-holder as the latter moves up to grasp the dog.
The drawbacks of this technique are, first, the great difficulty of selecting bulk parts from a vibrating bowl in order to send them along the rail on edge. With dogs of certain shapes, automatic selection is impossible and much more sophisticated techniques are required. Moreover, the device is not very reliable and often jams, so that the two retractable retainers do not always hold the dogs effectively, especially at the moment when the parts are to be gripped by the part-holder, with the result that dogs drop out onto the machine platform.